Conduits, such as pipes, hoses, pipelines, etc., adapted to convey fluids (liquids and gases) can be susceptible to rupture and leakage.
On aircraft, fuel pipes need to be protected against rupture and leaks, in particular when they traverse parts of the aircraft which may include ignition sources. A system is needed to quickly isolate those pipes so that any resultant fire is not fed by more fuel, and can be extinguished either by active means and/or fuel starvation.
This is particularly important where pipes traverse engine rotor burst zones. Typically on modern aircraft, essential services such as harnesses, hydraulic lines and fuel pipes are ensured by running them diversely such that any rotor burst event resulting in a release of material with high energy will not have a trajectory through both prime and redundant services. However this does not stop the release of fluids, fuel or gases from one of the ruptured lines, and those lines need to be isolated as quickly as possible.
It has been proposed that future aircraft may make use of hydrogen fuel cell technology. The hydrogen fuel tank is proposed to be in the tail of the aircraft and the fuel cell is proposed to be forward of that, and with the option of rear engines, the hydrogen carrying fuel pipes could traverse those engine's rotor burst zones.
In the field of oil and gas extraction and transportation, or any other environment where highly flammable or explosive fluids are transported via pipelines, a system is needed to halt the flow of fluids through the pipeline in the event of a potentially catastrophic failure.